But don't jump to the conclusion that Kate's eating for two. Earlier this month, the 29-year-old sparked pregnancy rumors when she refused peanut paste during her and William's visit to a Denmark UNICEF distribution center. (Although Kate is not allergic to peanuts, pregnant women are often advised to avoid peanut products to prevent allergies in their babies-to-be.)

But a royal insider explained to Us Weekly that Kate simply isn't "comfortable eating in front of cameras… What if she didn't like it and made a face? That expression would then be on every newspaper."

A spokesman for the couple told Us the policy is "to never confirm or deny [pregnancy] rumors," but an insider insists: "If and when there is an announcement to make, it will be made by the palace as soon as it's safe to."